Fluid pressure tool



April 18, 1933. G. M. NELL 1,904,694

FLUID PRESSURE TOOL Filed July 10, 1930 2 Sheets-Sheet 1 I3 (93 2. /2 11 JJ /7Q .Qw. X. 71m

A TTORNE Y.

x INVENTOR. z\\% asfcrre M /Ve// April 18; 1933. M NELL 1,904,694

FLUID PRES SURE TOOL Filed July 10, 1930 2 Sheets-Sheet 2 kid INVEN TOR. Gusfcw/e M. Nell A TTORNE Y.

Patented Apr. 18, 1933 ens'ravn M. NELL, OFDETRQIT, MiCIiIGA1I ASSIGNOR TO onrcaeo rnnn yrairic 'roor.

oomranvgor NEW Yo m, Y., AfooRronA'rron orivnwfannsny 1f Fmm 'rnnssunn roon Application filed July 10,

This invention relates to fluid pressure tools of the percussivetype having automatically actuated valve means for controllingthe distributionof the pressure fluid. i a A One object of the invention is to increase the economy of operation of toolsof'the described type; Another object is to devise valve mechanism-which will reduce the consumption of pressure fluid without correspondingly reducing the efficiency of the tool. Another object is to make such valve mechs 'anism simple, compact, and po'sitivein operation. Other objects will beapparent from the detailed description which follows i The invention involves the cutting" ofl of the pressure fluid supply at a predetermined position in the movement ofthe'piston and allowing a definite expansion to takeplace before the exhaust is opened. By preference:

there is a definite period in bothTth-e working and non-Working strokes of thejpiston when themain motive fluid supply is entirely cutoff and prevented from enteringthe pis ton chamber. y 149 In order to illustrate theinvention one con- 7 'crete embodiment thereof, isshown in the accompanying drawings, inwhich': r F ig. l'is alongitudinalsectionalview, largely diagrammatic and broken away ;in parts, showing the hammer piston beginning its working stroke; i Fig. 2 r is a fragmentary sectional view showing the position of the parts atthe time of the movement of the inner valve to cutoff the fluid supply to the rear end of thepiston chamber; Fig. 3 is a view similar to Fig. 1 showing the position of the 'parts at the timeflwhen the pistonstrikes its blow and begins the return movement; and

Fig. 4 is a'fragmentary view showing the piston on its rearward or non-working stroke at the point where the inner valve is moved 7 to cut offthefiuid supply.

' grammatically illustrated, the cylinder having therein a reciprocable piston 6 dividing thepiston chamber into a rearcylinder cham- -56 respectively at the opposite lendsof "the direction to cause-shifting oi the same; central groove or recess11'9 in the; exterior of this valve registers alternation" with .auxil- :iarylvent passages 2 1 and 22, which have 190 1930. Serial in. 466,929; i

ber fia' and a forward Piston 6is arrangedto impart blows to shank 7 ota drill steel supported ina front head 8 either directly or through an;ii;iterp9$6lfinvil block 9 1whichj; may be supported infa guide member or; bushing "10 interposed 1 between front head "8 and cylinder 5; andintelescoping relation with the-*s me.;ga Cylinder 5i-lfi as' a mamatmospheri-c exhaust-port 5'0 controlled by piston 6* and-overrun by the latter ini both dirccti nscf i m vementa, Y

iMotiv'e fluid for-actuating stes e vistas.

mitted-in accordance with the usual practice by a" throttle: valve (not shown) to inlet pas- "sages ll whence it is directed to, a valve chamber 5d providedby cylinder 5,. v-within the valve h m a e; uppor ed for reciproca- 4 tory movement'nestedrinnerand outerytubularvalves 12 and 131whichareautomatically 1 thrown in timed relation with the movement of piston 6 and both ofwhich controlthe ad mission of-p'ressure-fluid frominletl1;to passages, -14 .and1-15 lea-dingito chambers 5a5and cylinder. The ci'antral. bore throughinner motive :fluidfrominlet 11- vto passage 15, u

Valve, chamber; 5d"may be lined'fas shown by a bushing lfi slidab-ly receiving outer valve, i :5!

13 and have at its end-s bearing'members ,1? and '18 having annularprojections orfianges 17a andj18a for centering valves 12 and 13; V Inner gvalve 12 has-sliding telescoping engage- I projection 17a ,under control or both the :73? valve. l2serves as ajconduitjifor passing the valvesprovide for movementof motive fluid from inlet llvto passage; 1i while similar ports 18?) ;through bearingprojection 18w under control-of both valves provide for movement of pressure fiuid from thebore of inner valve 12 to ports 18d and thence to passage 15.

Outer valve13 has end areas 13a'and 13b subj ected to, air trapped .and compressed y the piston near the end of its stroke in eacili I 1 as i 60 7 k12 through ports 18b,*passages 18d and pasports opening into the piston chamber'on opposite'sides of main exhaust 50, and, connects the same to an atmospheric: vent 23; Similar- V a 27 respectivelyfor inner valve 12, communi= I ports ,24a and 25a through, valve 13 which of valve 13 on opposite sides of recess 19 regpassages26 an d'27.

recesses'or grooves 24; and25 in the exterior ister' at an times with shift passages 26 and cation with the latter beingestablished. byv

open adjacent pressurejare'as ion .jvalve'l'12' formed" by spaced radial, flanges 28 and. 29.

outer valve 13. Flanges 28 and 29 have restric'ted passages 28aan'd 29a therethrough F Theloperatio'n" ofthe tool may be descrilued as ffollowsz InFig. l'valve's 12 'andf1i3 are {both at'the leftor forward position thereby admitting motive fluid frominlet 1 1 through --prt's--17b' topassagell and'thence to chamber a to' drive piston 6 on" its working or "blow stroke; As the piston advance's' it;'closes main exhaust 50 but the air inI-advance of the pisa ton continues to escape through auxiliaryex- .haust passage'22fand recess 19 'in valve 13 to" 530' [piston 6 uncovers shirt passage 27', pressure fluid passes through othela'tter' andgbymean's of groove 'andport25ain valve 13 hasac'- 1 jc'e'ss' to. the pressure areaon inner -valve 12 Provided by flange29 with the resultthat the atmospheric vent-23,, When -the rear fend of j valve moves to its right or rearward position i IFig-$2),thereby closing portsY1'7 band out *ting-ofl admission-of inotive fluid to passage 141 The relative positions (sfhe moving! 7 flowof motive fluid'to' chamber 5abeing prevented b'y inne'r valve 12, and as valve'13 has rnot moved from its'original position, pressure;

parts are now sh'own'in Fig. 2; F-urther in- {and 15. Onl'a'ccount of the expansiveness of f the-motive fluid alreadyadmitted to chamber' '-5a,'the pistonwillgcontinue in they direction of;the1arrow with increased speed and force. Ju'st'before piston J6 strikesitsblow it closes auxiliary ventpassage 22 whereuponthe air' "in advance of the piston is trapped and "com-f pressed against the end. area 13b ofvalve :13 so th'at itoi's moved to the right'or' rearfposi- 7 tion, the piston having meanwhile overrun a sure "'in' cylinder chamber fiafandf upon the rearpressure face'13a ofthe valve;

main exhaust '50" and thereby reduced the pres- W'ththe parts now in the position shown in Fig. 3, motive fluid passes; 'from'linlet 1'1 down through the centralbore or inner valve sage 15fto cylinderohamber 5b to, drive piston 6, rearwardly,jthe' air inladvan'ce of the piston escapinglthrough main: "exhaust 5c and [after f that'is sealed through auxiliary'lexhaust pas-'1 the reduced passages 28a and 29awhich'do; 130

sage 21 which is now connected to atmos-E' pheric vent 23 by groove 19 in outer'valve 13. 'As the piston 6 moves rearwardly, it uncovers shift "passage v26 thereby admitting pressure fluid through groove 24 and port "(0 24a in valve 13 against theouter area of flange 28 on inner valve-12, causing the latter to movelto its left or; forwardposition (Fig. 4)to-close-por ts 18b and cut off the supplyof pressure fluid from the Lin'letgto passage 15. 75,;

The'parts are now inth'e position shown in withthe pressure fluid supply out ofi toboth ends ofthe piston chamber; Piston 1 V ".6 continuesv toiimove 'rea-rwardly by c pansion of the motive fluid already ad '50 'lnittedto chamber 56 and after'closing auxjiliary exhaust 21 the airtrapped in chamber 5 '5a isc'ompres'sed and made-efl'eetiveagainst .Liend area'13aoof outer valve 13' withthe re 1 w 7 sult that the latter also shifts to the left or forward position; as "piston 6fo'verruns' and jiuncover s v main e'xhaust;50.-, V This brings, the a movingparts aga n into the POSIlJIOIIS ShOWIL in Fig. plete: I -To be e g I essential that piston G be driven with full '1"and"the cyc'leof operation i 'c m *power and at 'n aximum speedfon the outward -or{ 'worki ng stroke; 1 Hence the vexpansion 7 V period for motive fluid on this stroke, .repre- -95. 1

:sented'subs'tantially bytheydistance between V auxiliary vent 2 7 andmain exhaust 50 (se'e s Fig.2 in particular), is "relatively brief and only suflicient'to-get the full e'ifect of the pres-" V sure-fluid admitted tochamber 5a,withoutf*1 0 checking the speed of piston 6.; On the back stroke,'however, the purposeis merely to rei turn piston 6 with a reasonable quickness but without power; hence 'inotive fluid is adniitted' toj chamber '55 for a -inuch'shorteri io period, as indicatedfby a; comparison of the 1 distance between'ladmission port-.15 and shift passage 26 at the'front' of the Cyligidehtviththe distancebetween'inlet"passage l lmand 7 *shift passage 27 at the rearend of the piston i chamber; Also the expansionperiod"onthe "backstroke is much longer since it covers substantially theqdistance betweenshift pas-Q sage 26 and main exhaust 5a Fromthe abovelit will be noted that both '115 of the nested'tubular valves "controlthe ad'- mission of pressurejfluid to the'oppos'ite ends I s or the piston chamberduejto the fact that both cover'andiuncover identicallythefsame f ports namely' 17 b and18b in the spacing andflj V ".Ib'e'aring projections 17d and "18a on bearingg members 1 7' and 18 respectively, and that the outer valve 13 controls theauxiliary vents 21 and 22 for the piston chamber andthe-admisf- :si'on'lo f pressure fluid from oylinder chamQ a bers 75a and 5b=through shift passages 26'and -27-'tothepressure areas provided by flanges 1 28 and 29 on valve 12.13am ofthesepres-g s c sure .areasare normally' "vented by ineansoif Y t fi'ective'as apercussive tool, it is i V -not interfere with the shifting of'the valve since they areof very small size'as compared with the area of the shift passages.

compact and positive in operation and provides for the expansion of the charge of pressure fluid fordriving the piston'inboth directions thereby effecting economy of operation without impairing the efflciencylof the tool. Small ports 31 and 32 may be provided if desired in the ends of outer valve 13..to

serve as priming ports for-starting thetool and to augment the fluid trapped by piston 6 in cylinder chambers 5aor 5b to trip valve 1 3.

While the invention has been herein disclosed in what is now considered to be a preferred form, it is to be understood that the invention is not limited to the specific details thereof but coversall changes, modifications,

and adaptations within the scope of the appended claims.

I claim as my invention: a V t r a v 1. A motive fluid operated motorhaving a cylinder, a pistonreciprocable therein and forming two cylinder chambers, and two pressure thrown valves each controlling ad mission of motive fluid to both of said chambers, one of said valves being tubularto provide a motive fluid passage axially therethrough for conducting the mainmotive fluid supply to one of said chambers.

2. A motive fluid operated motor having a cylinder, a piston'reciprocabletherein and forming two cylinder chambers,- and two pressure thrown valves each controlling admission of motive fluid to bothfof said chambers, said valves being'in nested relationand one of'them having a central axial bore providing a motive fluid passage therethroughfor conducting the main -motive fluid supply to oneof saidchambers. V v 3. A- motive fluid operated motor having a cylinder, a piston reciprocable therein and forming two cylinder chambers, andtwo pressure thrown valves each controlling ad mission of motive fluid. to both'of said chambers,.said valves'being tubular and in coaxial relation and providing an axial passage'entirely therethrough for the main motive fluid supply to one of said chambers.

4. A motive fluid operated percussive-tool having a cylinder, a piston I reciprocable therein, said cylinder having an exhaustport controlled bysaid piston and a passage lead- V 5. A motive fluid operated percussive toolhaving a cylinder, a piston reciproca'hle therein, said cylinder having axially spaced exhaust ports controlled by said-piston and passages leading from sai'dports to atmos- With- -this arrangement the valve structure is very phase, and we tu al valves in nested ale. scoped relationcontrolling the admission of motivefluid to the opposite ends ofsaid cyl inder to reciprocate said'piston, one of said valves controlling both said passages. i

6. A motivefluid operated-percussi e tool."

having. a .cylinder,, a piston-reiprocable therein, said cylinder having axially spaced 1 exhaust ports controlled by said .pistonaand, passages'leading from said ports to atmosphere, and two tubularvalvesinnestedi-tele inder. to' reciprocate saidpiston, one of said cylinder having shift:portsintermediate said valves controlling both said passages, said A exhaust ports and passages extending there- I "from for. tripping the other" of :said valves,

and. ports through the 'first ofgsaid valves ports is made available for trippingy-tli'esec- .ond valve.

through which motive fluid from said. shirt X x 7 A motive fluid operated percussivetool having a J cylinderpa piston" reciprocable therein, saidcylinder providing a-niain :ex haust and an auxliary exhaust ports both positioned so as to-be covered and uncovered by. said. piston, and F two valves controlling the admission of motivefluidto the. opposite" ing a passage leading from" said auxiliary exhaustport for control by one of said valves.

8.- A fluid pressure percussive tool having a cylinder, apiston reciprocabletherein, said haust port substantially cent ralliy thereof of said main. exhaust, all saidpo-rts 'beingunder control of said piston, two:valves both controlling the admission of; pressure "fluid tothe opposite ends of saidicylinder, and. passages leading'from said auxiliary exhaust ports under control of one of said valvesfi 9. A fluid pressure percussive tool having a cylinder, a piston reciprocable.therein,rsaid cylinder providing a. main atmospheric exhaust port substantially centrally v: thereor' and auxiliary exhaust'portsat opposite sides oflsaid main exhaust, all saidiports-being controlling the admission of pressure fluid to valv csby pressure "fluid admitted fromthe Ithe oppositeends of said cylinder, and"pas-. V sages leading from said 'auxiliary'iexhaust ports under control of oneofsaid-valves, 'and mea ns for shifting the other ofsaid- J piston chamber comprising'shift ports in said I 7,

cylinder intermediate said auxiliary exhausts and said main exhaust. Y

10. T A fluid pressure ope in'g inlsequen'ce to control' admission of motive fluid to both endsofthe-cylinder, a-shift "scoped relationcontrollingthe' admission of 7' motive'fluid to the opposite ends of saidcyl;

ends-of said cylinder, saidcylinder provid-u cylinder providing almain atmospheric ex and auxiliary exhaust ports-at opposite sides V under' controlofsaid pistom'two valveszb'oth e1 rated to01eQmip1 iSAi2 'ing a cylinder, a piston reciprocable therein, 'two. valves one within the other and shift- 7 area on one of said valves, and means include i I ia'A fluid pressure V ingatrip port intermediate the'endsof the icylinde'r under control of said piston and a Portfinthe. otherof said valves for directing 11a Afflliidrpressure tool having a'cyliiider,

V 1 "admission; of, motive 'fliiid'to said cylinder, .ffluidi pi'essure- I'rreansunder control of; said piston for'shiftingfsai'd valves in timed relation with: the "movement of said piston-,the

" -1 innerwof'said valves forming, a'i'con'duitfor o 'fmotiv eifluidforone end of said cylinder;

7 having a valve chamber, two- 1 tubular valves 7 Y trollingtheadmissionof motive fluidtosaid cylinder, andcentering means at the ends of said valve chambercomprising proj ections :engaged on opposite Y sides-bysaid valves and 1 25 portsritlirough-wsaidz projectionslz control led --hy both Valves; 1

toelhavi gfalcylim pider, apiston .reeiprocabletherein, sai'd'tool :having. a valve".chamb'er, tvvo tuhularvalves #80 inrnested'relatlon in saldchamber for*controlling the admission ofm otive fluid to said cylinder,-'.opp'osed pressure areas on the inner w of'said valves, means undercontrolof said piston for admitting' pressure fluid-from the 5 355 pistonchamber tosai d areas alternation i' Tito shiftgsaidevalvefland:cooperating means Z on: said "valvesfiwhereby saidfirst-named means are-controlled by the relativelpositions VI a 5, A fluid pressurewtool".havingia: cvlinr' 5 ,deryawpiston reciprocable therein, said tool having "a valve, chamber, two tubular valves in nested relation, in. said chamber for conthe piston oha'mber ato said 7 areas in alternayti'on to shift said'valve, cooperating meanslon -:'s'a1dvalveswherebysaid first-na ned-means- ;,are 1 controlled; by the relative positions of sai divalvesg'i' and means providing a restricted vent for ate-least oneofsaid'inner'va'lve areas including a portin said outer valve.-

55 C 15. A: fluid pressure' tool having 'a cylinder, :a:;pist0n reciprocahle therein, said tool I ,havingavalve chamber, twotubulalr valves in nested relation to said chamber forJconf areas, means controlled by saidgpiston :and hy the relative .positions of said valves for directing-s pressure fluid from,..t11e I 'piston V ,chamber tosaid areas in alternation to shift a piston reoiprocable therein, said tool having f lai valve.oliafnbentvvo tubular valves in nested f relation ;in said chamber: for controlling the g 1in nested rela'tion insaid chamber for c0n-:

"(valve providingopposed pressureareas and means on the other of said valves for admit- =tingpressure fluidptosaid'areasgin alterna- "tion. dependent fupon the; relative positions iofgsaid-valv'esb 1' ;:'h

*19. t In a v.fluid pressure percussive mot0r,' QQ

- communication with the, space; between said i trolling the "admission of niotiveifluid to said V V 5 'cylinder;opposed-pressureareas on-the in' 1 nerx'of-jsaidi valves, Ineans under control of saidlpiston foradmitting pressure fluid from tubular :valves in :nested telescoped relation,"- flanges on the innervalve providing opposed {pressure areas-and having restricted :ports therethrough, ,the outer valve, having ports v Ioontrolled by saidfflangesrfonadmittingsmo- 1 motor comprising a bushingzorcasing mem her, inner an'd outerztubular valvesin nested" relation within said bushing, the 'outervalve said inner valva'i and means providing controlling the 1 admission of motive flu-id] to said cylinder, theiinneriof said ,valves ha V- ling spacedgflanges'providingopposed pres- @175 i: .sure areas, means icontrolledby said-piston and By the 'relative positions lof saidivalves ifordirectingpressurefluid from the piston 1.

chamber toisaid areaslinl alternation to 7 shift 7 Y said'in'nervalve, said valve flanges havingrestricted bores.. tllerethrough, and means con- 12: 'fluid pressure tool having a cylina -derya piston 'reciprocable therein, said tool" tinuously':ventinggthejspace between said zflanges including a port in said outer valve.

scoping relation, means on one ofsaidvalves to provide opposed qpressure are'as, and? co- '-,operating meansHon said ,ivalve's providing fforiaccess of-ifmotlvetfluidto; sald areas 1n alternation dependentupon the relative-[po sitions .of said valves. v a 18; In a fluid pressure percussive }motor,

in? combination, two tubular valves in nested telescoplng relation, r flanges, on the inner 1 I V l r v '195 tubular valves in nested telescopedarelation, v

flanges on 'the inner-i valve-providingflop- ,e posed, pressure iareas, the outer valvehaving 7 ports, controlled; by saidiflanges fOIlifidHiitting. motive fluid in alternation'to said areasf and a vent port 'therethroughI.inioonstant flangesuf'; V V A.

2011-11, a. fluid pressure percussive; motor,"

tive' fluid in'oalternation to -.said areas "and a vent port ,therethrough jinficonstant commw' :nicatioh with. the space between said'flanges. 1 I 21. A valve assembly forIa fluid-pressure s'lidablyengaging said bushingg; end memev Ibers' ;for said Ehushing havingannular pro-j 'jections whose outer and innerisurfacespro videbearings for said valves, saidfprojed tions having," ports therethrough'i controlled 1 l by 'b othsaid valves;

q 22. A valve'assemblv motorz, comprising a bushing creasing mem- V 0 I 7 ber,. nner and outer tubular valves in nested e- 3 der, apiston reciprocable therein, saidtool 'm, having a valve chamber, two. tubular'valves in nested relation insaidchamberg1for con- I position to close said ports.

of July,1930.

relation within said bushing, the outer valve slidably engaging said bushing, end memhers for said bushing having annular projections whose outer and inner surfaces provide bearings for said valves, said projections having ports therethrough controlled by both said valves, andmeans on one of said valves for registration with the ports on one of said projections to pass a limited amount of motive fluid when the said valve is in 23. A valve assembly for a fluid pressure motor comprising a bushing or casing member, inner and outer tubular valves in nested relation within said bushing, the outer valve slidably engaging said bushing, end members for said bushing having annular projections whose outer and inner surfaces pro vide bearings for said valves, said projections having ports therethrough controlled by both said valves, and means on one of said valves for registrationwith said rojection ports in alternation topass on y a l limited amount of motive fluid when the said valve is in position to close said ports.

24. A valve assembly for a fluid pressure motor comprising a bushing or casing memwhen the valve is in position to close said last-named ports.

Signed by. me at Detroit, in the county of Wayne and State of Michigan this 3 day GUSTAVE M.INELL. 

